Tracking two decades of global gallium stocks and flows: A dynamic material flow analysis

Gallium (Ga) has recently garnered significant attention as a crucial byproduct element due to its crucial role in advancing low-carbon technologies and its globally imbalanced supply-demand. Understanding the global Ga flows and stocks can contribute to discovering ways to mitigate potential supply risks. In this study, we applied a material flow analysis to map the global Ga cycle from 2000 to 2021. Our results reveal the following results: (1) Over the past two decades, a cumulative 15.3% (313240.8 tons) of the total Ga reserves has been consumed through host metals (i.e., bauxite and zinc ores) mining. However, affected by actual demand, only 5549.7 tons of Ga have been extracted. Moreover, China has gradually become the dominant supplier of primary Ga globally, relying on its robust alumina industry. (2) The consumption pattern of global Ga is becoming increasingly complex. Driven by the diffusion of low-carbon technologies, primary Ga consumption has grown from 101 tons in 2000 to 432 tons in 2021. With a low material efficiency, only 2143.4 tons of Ga ultimately enter final products from semi-products. (3) The global Ga stock reached 956.7 tons in 2021 with significant recycling potential. However, commercial recycling systems were not established, and Ga resources in end-of-life (EoL) final products are mostly wasted. Given the anticipated growth of Ga demand, more coordinated efforts among different regions to promote technological innovation and improve recycling and circularity rates are urgently needed to ensure global Ga supply and a shared green future.